“Ligation of hemorrhoids (also known as rubber ring ligation of hemorrhoids, suction ligation of hemorrhoids and the like)” is a common method for treating hemorrhoids, the curative effect is exact, the principle thereof is to ligate a specially-made rubber ring (such as a rubber ring, a latex ring, a silicone ring and the like) on the roots (or the substrates) of hemorrhoids, to block blood supply to the hemorrhoids via the elastic retractive force of the rubber ring to induce necrosis, atrophy and fall-off of the hemorrhoids, so as to fulfill a cure purpose. Traditional instruments used for carrying out the ligation surgery are extremely simple, time-consuming and laborious to operate and are prone to leading to complications. To change this situation, over the past decade, an automatic instrument, namely, an automatic hemorrhoids ligation device (also known as a repeating hemorrhoids ligation device, a repeating hemorrhoids suction ligation device and the like), has been proposed to make the ligation surgery be simple and easy. The advantages of using the instrument to perform the ligation surgery are as follows: the operation is simple, convenient, fast and accurate; a single person can finish the surgery, and only 5-10 minutes are taken; the probability of complications is lower; patients generally need no anesthesia, and the pain is mild; most patients do not need to be hospitalized, so that the treatment cost is low.
The Chinese authorized utility model patents (ZL200820051521.X) discloses a repeating hemorrhoids suction ligation device, including a body, as well as a pipe body arranged at the front end of the body, a plurality of stretched rubber rings which are sleeved on the pipe body in sequence, a negative pressure suction joint arranged behind the pipe body and communicated with the inner cavity of the pipe body and a rubber ring popup device arranged on the body, wherein an emission head communicated with the inner cavity of the pipe body is sleeved on the front end of the pipe body, and the rubber rings are sleeved on the emission head; the rubber ring popup device includes at least one traction thread and a winding device arranged in the body, the front end of the traction thread is winded on the winding device; the tail end of the traction thread penetrates through the interior of the pipe body, is folded back from the orifice of the emission head and is connected with the rubber rings along the outer wall of the emission head through a traction mechanism.
The above-mentioned hemorrhoids suction ligation device (also known as a hemorrhoids ligation device) and other types of hemorrhoids ligation devices at home and abroad have a common feature, that is, “rubber rings” are used as basic materials which are ligated on the roots of hemorrhoids; available raw materials for making the rubber rings include natural rubber, latex or silica gel, etc.
The clinical efficacy of the rubber ring ligation of hemorrhoids is directly related to two technical indicators, namely, “internal aperture of the rubber ring” and “the elastic retractive force of the rubber ring”. The use of the rubber ring as the ligation material has some inherent disadvantages: (1) due to the inherent characteristics of the natural rubber (or latex or silica gel and the like), the internal aperture of the rubber ring cannot be infinitely small, and the rubber ring can be generally only made to 2.0-2.5 mm (at least not less than 1.5 mm), otherwise the rubber ring is easy to break when being stretched in a ligation process. This means that within the size range of the diameter of 2.0-2.5 mm (at least not less than 1.5 mm), the ligated hemorrhoids tissues are applied with no elastic retractive force, and finally, ulcer formed after tissue necrosis and fall-off ranges for about 2.0-2.5 mm (at least not less than 1.5 mm); (2) when the rubber rings are installed on the ligation device at a stretched state, the rubber rings are liable to fatigue gradually with time to increase the internal aperture; and (3) due to the influence of such factors as climate and environment and the like, the rubber rings are easy to age over time, so that the elastic retractive force becomes weaker.
Due to the influence of the above factors, the following consequences will be generated possibly: (1) rubber ring slippage occurs within a short period after the surgery, resulting in treatment failure; (2) postoperative bleeding complications are generated (according to statistics, the postoperative bleeding rate of the rubber ring ligation of hemorrhoids is 2-5%); and (3) hemorrhoids block necrosis is incomplete, healing of the ulcer surface is delayed and the efficacy is influenced.